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<table width="100%" summary="page for nasturtium"><tr><td>nasturtium</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Dose-response profile of degradation of agrochemical using nasturtium</h2>

<h3>Description</h3>

<p>Estimation of the degradation profile of an agrochemical based on soil samples at depth 0-10cm
from a calibration experiment.
</p>


<h3>Usage</h3>

<pre>data(nasturtium)</pre>


<h3>Format</h3>

<p>A data frame with 42 observations on the following 2 variables.
</p>

<dl>
<dt><code>conc</code></dt><dd><p>a numeric vector of concentrations (g/ha)</p>
</dd>
<dt><code>weight</code></dt><dd><p>a numeric vector of plant weight (mg) after 3 weeks' growth</p>
</dd>
</dl>



<h3>Details</h3>

<p>It is an experiment with seven concentrations and six replicates per concentration. <em>Nasturtium</em>
is sensitive and its weight reduces noticeable at low concentrations.
</p>
<p>Racine-Poon (1988) suggests using a three-parameter log-logistic model.
</p>


<h3>Source</h3>

<p>Racine-Poon, A. (1988) A Bayesian Approach to Nonlinear Calibration Problems, 
<em>J. Am. Statist. Ass.</em>, <b>83</b>, 650&ndash;656.
</p>


<h3>Examples</h3>

<pre>

nasturtium.m1 &lt;- drm(weight~conc, data=nasturtium, fct = LL.3())

modelFit(nasturtium.m1)

plot(nasturtium.m1, type = "all", log = "", xlab = "Concentration (g/ha)", ylab = "Weight (mg)")
</pre>


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